Transcranial magnetic stimulation (rTMS) is an investigational and therapeutic modality that
impacts the connection strength between neurons by delivering patterned energy. In response
to this patterned energy neurons fire and adapt by changing their connection strengths. This
change in connection strengths is believed to be the underlying mechanism whereby this
intervention has therapeutic benefit for this intervention in conditions such as depression.
The purpose of this study is to test a means of enhancing the effect of rTMS using a
medication (cycloserine) that has been shown to augment and stabilize activity dependent
neuronal changes. The investigators wish to use the motor system, where the associated muscle
response to brain stimulation can be measured, to probe activity dependent changes in
connection strength between neurons.